Stock flow apron for a fourdrinier wire



Uct. 25, 196

W.VN. BENNETT 3,281,334

STOCK FLOW APRON FOR A FOURDRINIER WIRE Filed Feb. 21, 1964 H MM H IX/ZZZ tam/YT 56/2 9 United States Patent Ofiflce 3,Z8l,3ll Patented Get. 25, 1966 3 281 314 STOCK FLOW APRONFOfi A FOURDRINIER WIRE William N. Bennett, Fitchburg, Mass, assignor to Fitchburg Paper Company, Fitchburg, Mass, a corporation of Delaware Filed Feb. 21, 1964, Ser. No. 346,468 6 Claims. (Cl. 162-353) This invention relates to a new and improved flow of paper pulp stock from the headbox or flow control box on the apron to the Fourdrinier wire. It has been found that where pond sides, or guides in the nature of deckles are utilized at the sides of the apron just downriver of the slice to direct the pulp and to tend to keep the stock from flowing off the edges of the apron, certain frictional eddies and consequent high and low spots are created due to the drag of the stock along these boards. On the other hand, if these guide boards are not present, the stock will run off the side edges of the apron to an unwanted degree and in doing so cause low areas along the side edges of the paper formation. Wit-h a predetermined amount of stock flowing from the slice onto the apron, any appreciable amount of stock flowing off the apron at the side edges thins the stock in the area of the edges and this shows up in the finished product which has to be shaved or sheared, thus wasting the paper.

It is the general object of this invention to provide for side board guides at least partly along the apron and adjacent the slice, these guides being laterally adjustable to and from the edge of the apron, so that a small gap can be left between the side guides and the edges of the apron, allowing a small amount of the fluid stock to escape from the edges of the apron, but not to a wasteful degree, it having been found with this release of a small amount of stock there is no evidence of drag or friction of the paper stock along the edges of the apron down from the side guides, but on the other hand the stock flows freely and evenly from the ends of the guides down onto the Fourdrinier wire, resulting in a level formation which does not have thin edge portions.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawings, in which:

FIG. 1 is a diagrammatic view in side elevation illustrating the location of the invention relative to the paper making machine;

FIG. 2 is a view in front elevation, looking in the direction of arrow 2 in FIG. 1;

FIG. 3 is a view on an enlarged scale illustrating the adjustment of the side boards or guides, and

FIG. 4 is a diagrammatic view illustrating the action of the stock on the apron where the side guides are positioned close to the edges of the apron.

In illustrating the invention only so much of the machine is shown as to explain the nature of the invention. In FIG. 1 the reference numeral iudicatesa headbox of any construction provided with the usual slice through which the stock flows along the apron 12 onto the Fourdrinier wire 14, the breast roll being indicated at 16. The slice is shown at 18 in FIG. 2.

Arranged at each side of the apron 12 adjacent the slice are a pair of side boards or guides for the apron, these being indicated at 20. The function of these side guides is to prevent excess falloif of the fluid stock as it issues from the slice onto the apron and to thus assist in guiding the stock along the apron to the wire. The side boards or guides 20 may be as long as required for the particular installation involved but in every case as shown diagrammatically in FIG. 4, eddies are set up due to the drag or friction of the fluid as it passes along these guides. This deformation of the cascading fluid is quite obvious to the eye and it results in the high ridges or wakes 22 with correspondingly low or thin areas 24, 24 which also appear centrally of the apron in the area 26. Unfortunately this deformation shows up in the formation of the end product and results in paper which is not uniformly level from side to side. On the other hand, if the side walls or guides 20 should be removed, too much stock would flow over the edges of the apron and thin areas at the edges of the stock would be the result as the paper web is formed, thus resulting in waste edges which have to be sheared off.

In the present invention the side boards or guides 20, 20 are mounted for lateral adjustment, i.e., they are mounted for motion in directions normal to the planes thereof. Any way of supporting the side walls 20, 20 may be utilized as for instance some kind of brackets 28 extending from the front wall of the headbox. If these brackets are provided with transverse slide rods 30 mounting the side guides 20 slidably thereon, it will be seen that th guides 20, 20 can be adjusted to and from the edges of the apron 12. Any kind of adjustment may be utilized for this purpose as for instance a rotatable rod 32 having right and left-hand threads as at 34, 36 engaged in threaded openings in the guides 20, 20. Then if the rod 32 be rotated as for instance by a handle wheel or a crank 38, the side walls are seen to be adjustable to and from the edges of the apron. Each side guide can be adjusted independently if desired.

It has been found that in ordinary circumstances a very small opening between the edges of the apron and the side guides is very advantageous. The fluid which contacts the side guides when there is a small gap between the edges of the apron and the side guides and upon which drag might be expected to be impressed, is that fluid which is lost and flows off the edges of the apron, leaving all of the stock between the edges of the apron completely unimpaired and uninfluenced in any way by the side guides, except for the fact that excess of stock lost over the edges is avoided by the presence of the side walls even though they do not contact the edges of the apron.

It takes very little visual experimentation to find the exact setting needed for the particular stock involved to avoid the eddies or high spots at 22 or on the other hand to bring an excess of loss which would form thin spots along the edges of the stock. Once the correct distance for the particular stock is found, this can be utilized whenever similar stock is provided in the machine.

From the above description it will thus be seen that an improved fluid flow controlling construction has been provided which not only finds utility in the paper imaking arts but also is usable in any environment where fluid flowing down a ramp like surface must be prevented from excessively pouring over the sides thereof while at the same time maintaining a substantially even distribution across said surface.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is:

l. In a paper making machine, the combination comprising (a) a source of fluid paper stock;

(b) a Fourdrinier wire;

(c) an apron extending from said source of fluid paper stock to said Fourdrinier wire to direct fluid paper stock from said source to said wire;

(d) said apron including an upper surface upon which said fluid paper stock flows, a lower surface and a pair of side edges;

(e) a pair of selectively movable side guides each disposed in juxtaposition to one of said side edges of said apron for coaction therewith to direct and guide fluid paper stock from said source to said wire and each extending from a first predetermined plane below said upper surface of said apron to a second predetermined plane above said upper surface of said apron; and

(f) mounting means adjustably mounting said side guides for selective movement towards or away from said side edges respectively of said apron to provide gaps of predetermined dimensions between said side guides and said edges of said apron.

2. The construction of claim 1 wherein said first predetermined plane is below said lower surface of said apron.

3. The construction of claim 1 wherein said mounting means includes:

(a) a pair of fixedly positioned slide rods upon which said side guides are slidably disposed;

(b) a drive rod having formed thereon oppositively wound threads; and

(c) corresponding threaded means carried by said side guides for coaction with said threads on said drive rod.

4. Apparatus for delivering a fluid from a supply source to a utilization device comprising:

(a) fluid directing means leading from the source to said utilization device, said fluid directing means having an upper surface over which the fluid flows, a lower surface, and a pair of side edges extending in the direction of fluid flow;

(b) a selectively adjustable fluid guide element disposed adjacent each of said side edges of said fluid directing means and extending from a position below said upper surface of said fluid direction means to a position above said upper surface of said fluid directing means;

(0) adjusting means mounting said fluid guide elements for selective movement towards and away from their respective side edges of said fluid directing means to provide gaps of selected sizes between said fluid guide elements and said fluid directing means.

5. The apparatus of claim 4 wherein said fluid guide elements extend below said lower surface of said fluid directing means.

6. The apparatus of claim 4 wherein:

(a) said adjusting means includes a pair of fixedly disposed slide means slidably mounting said fluid guide elements and a rotatably disposed drive means having formed thereon oppositely wound screw threads; and

(b) said fluid guide elements each include a threaded portion disposed for coaction with a corresponding threaded portion of said drive means.

References Cited by the Examiner UNITED STATES PATENTS 933,656 9/1909 Millard 162336 2,677,316 5/1954 Heys 162-337 2,881,675 4/1959 Thomas 162310 2,904,461 9/1959 Washburn et a1. 162344 2,956,623 10/1960 Ikavalko 162336 DONALL H. SYLVESTER, Primary Examiner.

J. H. NEWSOME, Assistant Examiner. 

4. APPARATUS FOR DELIVERING A FLUID FROM A SUPPLY SOURCE TO A UTILIZATION DEVICE COMPRISING: (A) FLUID DIRECTING MEANS LEADING FROM THE SOURCE TO SAID UTILIZATION DIVICE, SAID FLUID DIRECTING MEANS HAVING AN UPPER SURFACE OVER WHICH THE FLUID FLOWS, A LOWER SURFACE, AND A PAIR OF SIDE EDGES EXTENDING IN THE DIRECTION OF FLUID FLOW; (B) A SELECTIVELY ADJUSTABLE FLUID GUIDE ELEMENT DISPOSED ADJACENT EAHC OF SAID SIDE EDGES OF SAID FLUID DIRECTING MEANS AND EXTENDING FROM A POSITION BELOW SAID UPPER SURFACE OF SAID FLUID DIRECTION MEANS TO A POSITION ABOVE SAID UPPER SURFACE OF SAID FLUID DIRECTING MEANS; (C) ADJUSTING MEANS MOUNTING SAID FLUID GUIDE ELEMENTS FOR SELECTIVE MOVEMENT TOWARDS AND AWAY FROM THEIR RESPECTIVE SIDE EDGES OF SAID FLUID DIRECTING MEANS TO PROVIDE GAPS OF SELECTED SIZES BETWEEN SAID FLUID GUIDE ELEMENTS AND SAID FLUID DIRECTING MEANS. 